Weingrad may be on firmer ground with the more limited claim that there are no Jewish fantasy writers as important as J.R.R. Tolkien and C.S. Lewis, by far the two most influential writers in the field. However, given the small proportion of Jews in the population, it’s quite possible that the two most influential writers in any given literary genre could turn out to be non-Jews just by chance alone – even if Jewish writers were no less attracted to that genre then gentiles. There are no European Jewish writers of traditional realistic novels who are as influential as Tolstoy and Dostoyevsky. In English-language literature, there are no conventional Jewish novelists as influential as Jane Austen and Mark Twain. But it would be a mistake to therefore conclude that prominent Jewish novelists are “strikingly rare.” To the contrary, it’s obvious that there are many more prominent Jewish novelists than one would predict based on their percentage of the populations of Europe and the US.

Finally, Weingrad also argues that there are few if any Jewish fantasy novels that are based on Jewish religious tradition in the same way that C.S. Lewis’ work is based on Christianity. As Nussbaum points out, this claim is probably true. The simple explanation here is that most Jewish fantasy writers are secular in orientation. That’s also true of most gentile fantasy writers of the last several decades. Even among gentile fantasy writers, Lewis was somewhat unusual in using his fantasy novels to promote traditional religious views. There are probably more prominent fantasy writers who have used their work to attack traditional Christianity (Marion Zimmer Bradley and Phillip Pullman are two of the best-known examples) than defend it.

UPDATE: Commenters have helpfully pointed out this list of prominent Jewish science fiction and fantasy writers.